This invention relates to snowmobiles. More particularly, it relates to a dolly system for facilitating movement of snowmobiles on floor surfaces.
Snowmobiles generally comprise a forward body portion which contains a motor, a rearward seat portion on which the passenger sits and which is positioned on top of a driven track member and two forward skis extending from the forward body portion. Typically, snowmobiling is a seasonal sport and the snowmobile will not be operational and will be in storage, such as in a garage for most of the year. Snowmobiles, although usually quite maneuverable under power in the snow, are quite heavy and cumbersome to move about on hard surfaces such as garage floors. To accommodate such movement, devices to make the snowmobile more mobile on floor surfaces are very useful. Such devices need to be secure and stable under the snowmobile to prevent the snowmobile from tipping or falling off of said devices, creating a risk of damage to the snowmobile or even personal injury. This is especially true where the floor surfaces are rough or there is debris on the floor. Moreover, in that such devices see limited use, they should be so constructed that the may be easily manufactured at minimal expense and, should be compact and easily storable during nonuse.
U.S. Pat. No. 3,881,740 to Bruce A. Johnson et al. describes a pallet with castors on which the snowmobile is placed. This apparatus has a disadvantage that for convenient loading of the snowmobile on the pallet, the machine must be powered or driven onto same. Additionally, the pallet is quite bulky and is collapsible for storage.
U.S. Pat. No. 3,860,078 discloses a three-piece dolly system which has forward dollies for placement under the snowmobile skis and a rearward dolly which engages with a snowmobile support rod at the rear end of the snowmobile. The forward dolly has a trough which receives a longitudinal steering rib on the skis. Contact between the ski dolly and snowmobile ski is limited to the horizontal top surface of the dolly's side rails. The trough is disclosed in the Stoick et al. patent as rectangular in configuration.
U.S. Pat. No. 4,288,087 to Morrison discloses a three-piece dolly system with two forward ski dollies. The ski dollies consist of an axle between two wheels and a crossbar attached to the axle and two longitudinal members affixed to the crossbar to form a H-bar member. Engagement between the ski and the ski dolly is along the longitudinal members on the exterior runner portion of the skis. The rearward dolly comprises a plate with a single castor mounted on the bottom portion of the plate. The ski dollies have a thumb screw to clamp down on the ski to secure the ski to the dolly.
Modern snowmobile skis uniformly have a centrally positioned and longitudinally extending wear bar on the lower surface of the snowmobile skis. Said wear bars are removable and various types and sizes of wear bars are available for specific applications. Many such wear bars have carbide portions which can easily damage even concrete floors.
The applicants are not aware of any prior art which utilizes forward dollies that grip and engage the wide variety of wear bars available and that also provide supplemental sidewall restraints.